Records |
Author |
Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. |
Title |
The role of the VZn-NO-H complex in the p-type conductivity in ZnO |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
17 |
Issue |
17 |
Pages |
5485-5489 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
|
Language |
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Wos |
000349616400080 |
Publication Date |
2015-01-20 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
20 |
Open Access |
|
Notes |
FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules |
Approved |
Most recent IF: 4.123; 2015 IF: 4.493 |
Call Number |
c:irua:123218 |
Serial |
3592 |
Permanent link to this record |
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|
Author |
Sankaran, K.; Clima, S.; Mees, M.; Pourtois, G. |
Title |
Exploring alternative metals to Cu and W for interconnects applications using automated first-principles simulations |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ECS journal of solid state science and technology |
Abbreviated Journal |
Ecs J Solid State Sc |
Volume |
4 |
Issue |
4 |
Pages |
N3127-N3133 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The bulk properties of elementary metals and copper based binary alloys have been investigated using automated first-principles simulations to evaluate their potential to replace copper and tungsten as interconnecting wires in the coming CMOS technology nodes. The intrinsic properties of the screened candidates based on their cohesive energy and on their electronic properties have been used as a metrics to reflect their resistivity and their sensitivity to electromigration. Using these values, the 'performances' of the alloys have been benchmarked with respect to the Cu and W ones. It turns out that for some systems, alloying Cu with another element leads to a reduced tendency to electromigration. This is however done at the expense of a decrease of the conductivity of the alloy with respect to the bulk metal. (C) 2014 The Electrochemical Society. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Electrochemical society |
Place of Publication |
Pennington (N.J.) |
Editor |
|
Language |
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Wos |
000349547900018 |
Publication Date |
2014-11-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2162-8769;2162-8777; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.787 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.787; 2015 IF: 1.558 |
Call Number |
c:irua:125296 |
Serial |
1150 |
Permanent link to this record |
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Author |
Meledina, M.; Turner, S.; Galvita, V.V.; Poelman, H.; Marin, G.B.; Van Tendeloo, G. |
Title |
Local environment of Fe dopants in nanoscale Fe : CeO2-x oxygen storage material |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
7 |
Issue |
7 |
Pages |
3196-3204 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Nanoscale Fe : CeO2-x oxygen storage material for the process of chemical looping has been investigated by advanced transmission electron microscopy and electron energy-loss spectroscopy before and after a model looping procedure, consisting of redox cycles at heightened temperature. Separately, the activity of the nanomaterial has been tested in a toluene total oxidation reaction. The results show that the material consists of ceria nanoparticles, doped with single Fe atoms and small FeOx clusters. The iron ion is partially present as Fe3+ in a solid solution within the ceria lattice. Furthermore, enrichment of reduced Fe2+ species is observed in nanovoids present in the ceria nanoparticles, as well as at the ceria surface. After chemical looping, agglomeration occurs and reduced nanoclusters appear at ceria grain boundaries formed by sintering. These clusters originate from surface Fe2+ aggregation, and from bulk Fe3+, which “leaks out” in reduced state after cycling to a slightly more agglomerated form. The activity of Fe : CeO2 during the toluene total oxidation part of the chemical looping cycle is ensured by the dopant Fe in the Fe1-xCexO2 solid solution, and by surface Fe species. These measurements on a model Fe : CeO2-x oxygen storage material give a unique insight into the behavior of dopants within a nanosized ceria host, and allow to interpret a plethora of (doped) cerium oxide-based reactions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000349473200046 |
Publication Date |
2015-01-13 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 7.367; 2015 IF: 7.394 |
Call Number |
c:irua:125299 |
Serial |
1828 |
Permanent link to this record |
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|
|
Author |
Muñoz, W.A.; Covaci, L.; Peeters, F.M. |
Title |
Disordered graphene Josephson junctions |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
91 |
Issue |
91 |
Pages |
054506 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A tight-binding approach based on the Chebyshev-Bogoliubov-de Gennes method is used to describe disordered single-layer graphene Josephson junctions. Scattering by vacancies, ripples, or charged impurities is included. We compute the Josephson current and investigate the nature of multiple Andreev reflections, which induce bound states appearing as peaks in the density of states for energies below the superconducting gap. In the presence of single-atom vacancies, we observe a strong suppression of the supercurrent, which is a consequence of strong intervalley scattering. Although lattice deformations should not induce intervalley scattering, we find that the supercurrent is still suppressed, which is due to the presence of pseudomagnetic barriers. For charged impurities, we consider two cases depending on whether the average doping is zero, i.e., existence of electron-hole puddles, or finite. In both cases, short-range impurities strongly affect the supercurrent, similar to the vacancies scenario. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000349436500001 |
Publication Date |
2015-02-06 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
|
Notes |
This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Methusalem funding of the Flemish Government. |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
c:irua:129192 |
Serial |
3961 |
Permanent link to this record |
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Author |
Angelakeris, M.; Li, Z.A.; Hilgendorff, M.; Simeonidis, K.; Sakellari, D.; Filippousi, M.; Tian, H.; Van Tendeloo, G.; Spasova, M.; Acet, M.; Farle, M. |
Title |
Enhanced biomedical heat-triggered carriers via nanomagnetism tuning in ferrite-based nanoparticles |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of magnetism and magnetic materials |
Abbreviated Journal |
J Magn Magn Mater |
Volume |
381 |
Issue |
381 |
Pages |
179-187 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Biomedical nanomagnetic carriers are getting a higher impact in therapy and diagnosis schemes while their constraints and prerequisites are more and more successfully confronted. Such particles should possess a well-defined size with minimum agglomeration and they should be synthesized in a facile and reproducible high-yield way together with a controllable response to an applied static or dynamic field tailored for the specific application. Here, we attempt to enhance the heating efficiency in magnetic particle hyperthermia treatment through the proper adjustment of the core-shell morphology in ferrite particles, by controlling exchange and dipolar magnetic interactions at the nanoscale. Thus, core-shell nanoparticles with mutual coupling of magnetically hard (CoFe2O4) and soft (MnFe2O4) components are synthesized with facile synthetic controls resulting in uniform size and shell thickness as evidenced by high resolution transmission electron microscopy imaging, excellent crystallinity and size monodispersity. Such a magnetic coupling enables the fine tuning of magnetic anisotropy and magnetic interactions without sparing the good structural, chemical and colloidal stability. Consequently, the magnetic heating efficiency of CoFe2O4. and MnFe2O4 core-shell nanoparticles is distinctively different horn that of their counterparts, even though all these nanocrystals were synthesized under similar conditions. For better understanding of the AC magnetic hyperthermia response and its correlation with magnetic-origin features we study the effect of the volume ratio of magnetic hard and soft phases in the bimagnetic core-shell nanocrystals. Eventually, such particles may be considered as novel heating carriers that under further biomedical functionalization may become adaptable multifunctional heat-triggered nanoplatforms. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000349361100027 |
Publication Date |
2014-12-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-8853; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.63 |
Times cited |
20 |
Open Access |
|
Notes |
312483 Esteem2; Esteem2_ta |
Approved |
Most recent IF: 2.63; 2015 IF: 1.970 |
Call Number |
c:irua:125284 c:irua:125284 |
Serial |
1049 |
Permanent link to this record |
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|
|
Author |
Yalcin, A.O.; Goris, B.; van Dijk-Moes, R.J.A.; Fan, Z.; Erdamar, A.K.; Tichelaar, F.D.; Vlugt, T.J.H.; Van Tendeloo, G.; Bals, S.; Vanmaekelbergh, D.; Zandbergen, H.W.; van Huis, M.A.; |
Title |
Heat-induced transformation of CdSe-CdS-ZnS coremultishell quantum dots by Zn diffusion into inner layers |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Chemical communications |
Abbreviated Journal |
Chem Commun |
Volume |
51 |
Issue |
51 |
Pages |
3320-3323 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In this work, we investigate the thermal evolution of CdSeCdSZnS coremultishell quantum dots (QDs) in situ using transmission electron microscopy (TEM). Starting at a temperature of approximately 250 °C, Zn diffusion into inner layers takes place together with simultaneous evaporation of particularly Cd and S. As a result of this transformation, CdxZn1−xSeCdyZn1−yS coreshell QDs are obtained. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000349325000004 |
Publication Date |
2014-11-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1359-7345;1364-548X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.319 |
Times cited |
21 |
Open Access |
OpenAccess |
Notes |
262348 Esmi; Fwo; 246791 Countatoms; 335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 6.319; 2015 IF: 6.834 |
Call Number |
c:irua:132582 |
Serial |
1412 |
Permanent link to this record |
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Author |
Ennaert, T.; Geboers, J.; Gobechiya, E.; Courtin, C.M.; Kurttepeli, M.; Houthoofd, K.; Kirschhock, C.E.A.; Magusin, P.C.M.M.; Bals, S.; Jacobs, P.A.; Sels, B.F. |
Title |
Conceptual frame rationalizing the self-stabilization of H-USY zeolites in hot liquid water |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
Volume |
5 |
Issue |
5 |
Pages |
754-768 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The wide range of liquid-phase reactions required for the catalytic conversion of biomass compounds into new bioplatform molecules defines a new set of challenges for the development of active, selective, and stable catalysts. The potential of bifunctional Ru/H-USY catalysts for conversions in hot liquid water (HLW) is assessed in terms of physicochemical stability and long-term catalytic performance of acid sites and noble metal functionality, as probed by hydrolytic hydrogenation of cellulose. It is shown that zeolite desilication is the main zeolite degradation mechanism in HLW. USY zeolite stability depends on two main parameters, viz., framework and extra-framework aluminum content. The former protects the zeolite lattice by counteracting hydrolysis of framework bonds, and the latter, when located at the external crystal surface, prevents solubilization of the zeolite framework which is the result of its low water-solubility. Hence, the hot liquid water stability of commercial H-USY zeolites, in contrast to their steam stability, increased with decreasing Si/AI ratio. As a result, mildly steamed USY zeolites containing a high amount of both Al species exhibit the highest resistance to HLW. During an initial period of transformations, Al-rich zeolites form additional protective extra-framework Al species at the outer surface, self-stabilizing the framework. A critical bulk Si/AI ratio of 3 was determined whereby USY zeolites with a lower Si/AI ratio will self-stabilize over time. Besides, due to the initial transformation period, the accessibility of the catalytic active sites is extensively enhanced resulting in a material that is more stable and drastically more accessible to large substrates than the original zeolite. When these findings are applied in the hydrolytic hydrogenation of cellulose, unprecedented nearly quantitative hexitol yields were obtained with a stable catalytic system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000349275300031 |
Publication Date |
2014-12-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2155-5435;2155-5435; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
10.614 |
Times cited |
65 |
Open Access |
OpenAccess |
Notes |
335078 Colouratom; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 10.614; 2015 IF: 9.312 |
Call Number |
c:irua:125288 |
Serial |
474 |
Permanent link to this record |
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Author |
Van Holsbeke, C.S.; Leemans, G.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Geldof, M.; Verdonck, P.R.; Parizel, P.M.; van Schil, P.E.; de Backer, W.A. |
Title |
Functional Respiratory Imaging as a tool to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Respiratory care |
Abbreviated Journal |
Resp Care |
Volume |
|
Issue |
|
Pages |
1-20 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) |
Abstract |
In two subjects with a unilateral diaphragmatic paralysis and complaints of dyspnea, a completely different treatment approach was chosen despite similar anatomical and physiological abnormalities. These decisions were supported by the results generated by Functional Respiratory Imaging (FRI). FRI was able to generate functional information with respect to lobar ventilation and local drug deposition. In one subject, it was found that some lobes were poorly ventilated and drug deposition simulation showed that some regions were undertreated. This subject underwent a diaphragm plication to restore the ventilation. In the other subject, it was found that all lobes were still ventilated. A conservative approach with regular follow-up was chosen to wait for spontaneous recovery of the diaphragmatic function. Both subjects improved subjectively and objectively. These cases demonstrate how novel medical imaging techniques such as FRI can be used to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Dallas, Tex. |
Editor |
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Language |
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Wos |
000349200100024 |
Publication Date |
2013-12-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0020-1324;1943-3654; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.733 |
Times cited |
5 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 1.733; 2013 IF: 1.840 |
Call Number |
UA @ lucian @ c:irua:112982 |
Serial |
1303 |
Permanent link to this record |
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Author |
Colin D. Judge, Nicolas Gauquelin, Lori Walters, Mike Wright, James I. Cole, James Madden, Gianluigi A. Botton, Malcolm Griffiths |
Title |
Intergranular fracture in irradiated Inconel X-750 containing very high concentrations of helium and hydrogen |
Type |
A1 Journal Article |
Year |
2015 |
Publication |
Journal of Nuclear Materials |
Abbreviated Journal |
|
Volume |
457 |
Issue |
457 |
Pages |
165-172 |
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
Abstract |
In recent years, it has been observed that Inconel X-750 spacers in CANDU reactors exhibits lower ductility with reduced load carrying capacity following irradiation in a reactor environment. The fracture behaviour of ex-service material was also found to be entirely intergranular at high doses. The thermalized flux spectrum in a CANDU reactor leads to transmutation of 58Ni to 59Ni. The 59Ni itself has unusually high thermal neutron reaction cross-sections of the type: (n, γ), (n, p), and (n, α). The latter two reactions, in particular, contribute to a significant enhancement of the atomic displacements in addition to creating high concentrations of hydrogen and helium within the material. Microstructural examinations by transmission electron microscopy (TEM) have confirmed the presence of helium bubbles in the matrix and aligned along grain boundaries and matrix–precipitate interfaces. Helium bubble size and density are found to be highly dependent on the irradiation temperature and material microstructure; the bubbles are larger within grain boundary precipitates. TEM specimens extracted from fracture surfaces and crack tips provide information that is consistent with crack propagation along grain boundaries due to the presence of He bubbles. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000349169100022 |
Publication Date |
2014-11-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
|
ISBN |
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Additional Links |
|
Impact Factor |
|
Times cited |
29 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
EMAT @ emat @ |
Serial |
4540 |
Permanent link to this record |
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Author |
Silva, A.L.M.; Carvalho, M.L.; Janssens, K.; Veloso, J.F.C.A. |
Title |
A large area full-field EDXRF imaging system based on a THCOBRA gaseous detector |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
Volume |
30 |
Issue |
2 |
Pages |
343-352 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
By taking advantage of the attractive features in terms of gain, position and energy resolution of the 2D-THCOBRA detector, a new large area Full-Field X-ray Fluorescence Imaging (FF-XRFI) system for EDXRF imaging applications was developed. The proposed FF-XRFI system has an active area of 10 x 10 cm(2) and can be used to examine macroscopic samples with a moderately good energy resolution (< 1.6 keV FWHM at 8 keV) and a suitable spatial resolution (similar to 500 mu m FWHM). This combination of characteristics allows us to record elemental distribution maps from the surface of different sample types by combining image and energy information. Two different approaches were used for X-ray optics, one based on a single pinhole and another based on a parallel multiple-hole collimator. To illustrate the system capabilities, some sample examples were imaged and studied. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000349145700003 |
Publication Date |
2014-10-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.379 |
Times cited |
11 |
Open Access |
|
Notes |
; The authors thank Stijn Legrand for acquisition of the MAXRF maps shown in Fig. 15. This work was partially supported by projects CERN/FP/123604/2011 FEDER, COMPETE and FCT (Lisbon) programs. A. L. M. Silva is supported by the QREN programme Mais Centro – Programa Operacional Regional do Centro, FEDER and COMPETE, through the project Biomaterials for Regenerative Medicine (CENTRO-07-ST24-FEDER-002030). ; |
Approved |
Most recent IF: 3.379; 2015 IF: 3.466 |
Call Number |
UA @ admin @ c:irua:125297 |
Serial |
5452 |
Permanent link to this record |
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Author |
Sadeghi, A.; Neek-Amal, M.; Berdiyorov, G.R.; Peeters, F.M. |
Title |
Diffusion of fluorine on and between graphene layers |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
91 |
Issue |
91 |
Pages |
014304 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using first-principles calculations and reactive force field molecular dynamics simulations, we study the structural properties and dynamics of a fluorine (F) atom, either adsorbed on the surface of single layer graphene (F/GE) or between the layers of AB stacked bilayer graphene (F@ bilayer graphene). It is found that the diffusion of the F atom is very different in those cases, and that the mobility of the F atom increases by about an order of magnitude when inserted between two graphene layers. The obtained diffusion constant for F/GE is twice larger than that experimentally found for gold adatom and theoretically found for C-60 molecule on graphene. Our study provides important physical insights into the dynamics of fluorine atoms between and on graphene layers and explains the mechanism behind the separation of graphite layers due to intercalation of F atoms. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000349125800002 |
Publication Date |
2015-01-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
15 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:132561 |
Serial |
4161 |
Permanent link to this record |
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Author |
Deng, S.; Kurttepeli, M.; Cott, D.J.; Bals, S.; Detavernier, C. |
Title |
Porous nanostructured metal oxides synthesized through atomic layer deposition on a carbonaceous template followed by calcination |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
Volume |
3 |
Issue |
3 |
Pages |
2642-2649 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Porous metal oxides with nano-sized features attracted intensive interest in recent decades due to their high surface area which is essential for many applications, e.g. Li ion batteries, photocatalysts, fuel cells and dye-sensitized solar cells. Various approaches have so far been investigated to synthesize porous nanostructured metal oxides, including self-assembly and template-assisted synthesis. For the latter approach, forests of carbon nanotubes are considered as particularly promising templates, with respect to their one-dimensional nature and the resulting high surface area. In this work, we systematically investigate the formation of porous metal oxides (Al2O3, TiO2, V2O5 and ZnO) with different morphologies using atomic layer deposition on multi-walled carbon nanotubes followed by post-deposition calcination. X-ray diffraction, scanning electron microscopy accompanied by X-ray energy dispersive spectroscopy and transmission electron microscopy were used for the investigation of morphological and structural transitions at the micro- and nano-scale during the calcination process. The crystallization temperature and the surface coverage of the metal oxides and the oxidation temperature of the carbon nanotubes were found to produce significant influence on the final morphology. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000348990500019 |
Publication Date |
2014-12-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2050-7488;2050-7496; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.867 |
Times cited |
23 |
Open Access |
OpenAccess |
Notes |
Fwo; 239865 Cocoon; 335078 Colouratoms; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 8.867; 2015 IF: 7.443 |
Call Number |
c:irua:125298 |
Serial |
2673 |
Permanent link to this record |
|
|
|
Author |
Buczyńska, A.J.; Geypens, B.; Van Grieken, R.; De Wael, K. |
Title |
Optimization of sample clean-up for the GC-C-IRMS and GC-IT-MS analysis of PAHs from air particulate matter |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
Volume |
119 |
Issue |
|
Pages |
83-92 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The optimization of sample clean-up for the analysis of air particulate matter PAHs stable carbon isotope ratio using Solid Phase Extraction (SPE) cartridges is described in this paper. Various adsorbents, such as silica gel, alumina, florisil, commercially available for sample purification were compared. Best performance for the clean-up of 24-h air particulate matter samples was obtained with activated silica-gel columns in terms of selectivity and reproducibility. One step clean-up was optimized for concentration determination and in case of co-elutions, a second step was additionally used for carbon isotope ratio analysis. The method was subsequently validated with standard reference material and was checked for carbon isotope fractionation artefacts. No significant differences in δ13C values were found for unprocessed solutions of PAHs and solution subjected to the extraction and purification procedure. The procedure was tested on air particulate matter samples collected in three different locations in Belgium. Statistically significant differences in carbon isotope ratio of PAHs between Borgerhout location and Zelzate or Gent were noticed, confirming the differences in distribution and diagnostic ratios found during the concentration analyses and different PAH sources in these locations. The results, therefore, seem very promising for the use of δ13C of PAHs as an additional information helpful in source identification of these pollutants |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000348957800013 |
Publication Date |
2014-11-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.034 |
Times cited |
7 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.034; 2015 IF: 2.746 |
Call Number |
UA @ admin @ c:irua:120641 |
Serial |
5759 |
Permanent link to this record |
|
|
|
Author |
Retuerto, M.; Yin, Z.; Emge, T.J.; Stephens, P.W.; Li, M.R.; Sarkar, T.; Croft, M.C.; Ignatov, A.; Yuan, Z.; Zhang, S.J.; Jin, C.; Paria Sena, R.; Hadermann, J.; Kotliar, G.; Greenblatt, M.; |
Title |
Hole doping and structural transformation in CsTl1-xHgxCl3 |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
54 |
Issue |
54 |
Pages |
1066-1075 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
CsTlCl3 and CsTlF3 perovskites have been theoretically predicted to be superconductors when properly hole-doped. Both compounds have been previously prepared as pure compounds: CsTlCl3 in a tetragonal (I4/m) and a cubic (Fm3̅m) perovskite polymorph and CsTlF3 as a cubic perovskite (Fm3̅m). In this work, substitution of Tl in CsTlCl3 with Hg is reported, in an attempt to hole-dope the system and induce superconductivity. The whole series CsTl1xHgxCl3 (x = 0.0, 0.1, 0.2, 0.4, 0.6, and 0.8) was prepared. CsTl0.9Hg0.1Cl3 is tetragonal as the more stable phase of CsTlCl3. However, CsTl0.8Hg0.2Cl3 is already cubic with the space group Fm3̅m and with two different positions for Tl+ and Tl3+. For x = 0.4 and 0.5, solid solutions could not be formed. For x ≥ 0.6, the samples are primitive cubic perovskites with one crystallographic position for Tl+, Tl3+, and Hg2+. All of the samples formed are insulating, and there is no signature of superconductivity. X-ray absorption spectroscopy indicates that all of the samples have a mixed-valence state of Tl+ and Tl3+. Raman spectroscopy shows the presence of the active TlClTl stretching mode over the whole series and the intensity of the TlClHg mode increases with increasing Hg content. First-principle calculations confirmed that the phases are insulators in their ground state and that Hg is not a good dopant in the search for superconductivity in this system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
Language |
|
Wos |
000348887400048 |
Publication Date |
2014-12-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.857; 2015 IF: 4.762 |
Call Number |
c:irua:124420 |
Serial |
1476 |
Permanent link to this record |
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|
Author |
Carniato, L.; Schoups, G.; van de Giesen, N.; Seuntjens, P.; Bastiaens, L.; Sapion, H. |
Title |
Highly parameterized inversion of groundwater reactive transport for a complex field site |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of contaminant hydrology |
Abbreviated Journal |
|
Volume |
173 |
Issue |
|
Pages |
38-58 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
In this study a numerical groundwater reactive transport model of a shallow groundwater aquifer contaminated with volatile organic compounds is developed. In addition to advective-dispersive transport, the model includes contaminant release from source areas, natural attenuation, abiotic degradation by a permeable reactive barrier at the site, and dilution by infiltrating rain. Aquifer heterogeneity is parameterized using pilot points for hydraulic conductivity, specific yield and groundwater recharge. A methodology is developed and applied to estimate the large number of parameters from the limited data at the field site (groundwater levels, groundwater concentrations of multiple chemical species, point-scale measurements of soil hydraulic conductivity, and lab-scale derived information on chemical and biochemical reactions). The proposed methodology relies on pilot point parameterization of hydraulic parameters and groundwater recharge, a regularization procedure to reconcile the large number of spatially distributed model parameters with the limited field data, a step-wise approach for integrating the different data sets into the model, and high performance computing. The methodology was proven to be effective in reproducing multiple contaminant plumes and in reducing the prior parameter uncertainty of hydraulic conductivity and groundwater recharge. Our results further indicate that contaminant transport predictions are strongly affected by the choice of the groundwater recharge model and flow parameters should be identified using both head and concentration measurements. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000348878900004 |
Publication Date |
2014-12-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0169-7722 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:125290 |
Serial |
8041 |
Permanent link to this record |
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|
|
Author |
Schoelz, J.K.; Xu, P.; Meunier, V.; Kumar, P.; Neek-Amal, M.; Thibado, P.M.; Peeters, F.M. |
Title |
Graphene ripples as a realization of a two-dimensional Ising model : a scanning tunneling microscope study |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review: B: condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
91 |
Issue |
91 |
Pages |
045413 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Ripples in pristine freestanding graphene naturally orient themselves in an array that is alternately curved-up and curved-down; maintaining an average height of zero. Using scanning tunneling microscopy (STM) to apply a local force, the graphene sheet will reversibly rise and fall in height until the height reaches 60%-70% of its maximum at which point a sudden, permanent jump occurs. We successfully model the ripples as a spin-half Ising magnetic system, where the height of the graphene plays the role of the spin. The permanent jump in height, controlled by the tunneling current, is found to be equivalent to an antiferromagnetic-to-ferromagnetic phase transition. The thermal load underneath the STM tip alters the local tension and is identified as the responsible mechanism for the phase transition. Four universal critical exponents are measured from our STM data, and the model provides insight into the statistical role of graphene's unusual negative thermal expansion coefficient. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
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Wos |
000348762200011 |
Publication Date |
2015-01-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
|
Notes |
; This work was supported in part by Office of Naval Research (USA) under Grant No. N00014-10-1-0181 and National Science Foundation (USA) under Grant No. DMR-0855358. F. M. Peeters and M. Neek-Amal were supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
c:irua:123866 |
Serial |
1377 |
Permanent link to this record |
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|
|
Author |
Liao, L.; Heylen, S.; Vallaey, B.; Keulemans, M.; Lenaerts, S.; Roeffaers, M.B.J.; Martens, J.A. |
Title |
Photocatalytic carbon oxidation with nitric oxide |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Applied catalysis : B : environmental |
Abbreviated Journal |
Appl Catal B-Environ |
Volume |
166 |
Issue |
|
Pages |
374-380 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The photocatalytic oxidation of carbon black on TiO2 using nitric oxide as an oxidizing agent was investigated. Layer-wise deposited carbon and TiO2 powder was illuminated with UVA light in the presence of NO at parts per million concentrations in dry and hydrated carrier gas at a temperature of 150 degrees C. Carbon was photocatalytically converted mainly into CO2, and NO mainly into N-2. Carbon oxidation rates of 7.2 mu g/h/mgTiO(2) were achieved in the presence of 3000 ppm NO. Under these experimental conditions in the absence of molecular oxygen, formation of surface nitrates causing TiO2 photocatalyst deactivation is suppressed. Addition of water enhances surface nitrate formation and catalyst deactivation. NO and carbon particulate matter are air pollutants emitted by diesel engines. Elimination of soot collected on a diesel particulate filter through oxidation is a demanding reaction requiring temperatures in excess of 250 degrees C. The present study opens perspectives for a low-temperature regeneration strategy for the diesel particulate filter that simultaneously performs DeNO(x) reactions. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000348753400042 |
Publication Date |
2014-12-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0926-3373 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.446 |
Times cited |
5 |
Open Access |
|
Notes |
; This work was supported by long-term structural funding by the Flemish government (Methusalem). ; |
Approved |
Most recent IF: 9.446; 2015 IF: 7.435 |
Call Number |
UA @ admin @ c:irua:123858 |
Serial |
5977 |
Permanent link to this record |
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|
|
Author |
Colla, M.-S.; Amin-Ahmadi, B.; Idrissi, H.; Malet, L.; Godet, S.; Raskin, J.-P.; Schryvers, D.; Pardoen, T. |
Title |
Dislocation-mediated relaxation in nanograined columnar palladium films revealed by on-chip time-resolved HRTEM testing |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
6 |
Issue |
6 |
Pages |
5922 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The high-rate sensitivity of nanostructured metallic materials demonstrated in the recent literature is related to the predominance of thermally activated deformation mechanisms favoured by a large density of internal interfaces. Here we report time-resolved high-resolution electron transmission microscopy creep tests on thin nanograined films using on-chip nanomechanical testing. Tests are performed on palladium, which exhibited unexpectedly large creep rates at room temperature. Despite the small 30-nm grain size, relaxation is found to be mediated by dislocation mechanisms. The dislocations interact with the growth nanotwins present in the grains, leading to a loss of coherency of twin boundaries. The density of stored dislocations first increases with applied deformation, and then decreases with time to drive additional deformation while no grain boundary mechanism is observed. This fast relaxation constitutes a key issue in the development of various micro- and nanotechnologies such as palladium membranes for hydrogen applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000348742300002 |
Publication Date |
2015-01-05 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-1723; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
34 |
Open Access |
|
Notes |
Iap7/21; Fwo G012012n |
Approved |
Most recent IF: 12.124; 2015 IF: 11.470 |
Call Number |
c:irua:122045 |
Serial |
731 |
Permanent link to this record |
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|
|
Author |
Galvan Moya, J.E.; Nelissen, K.; Peeters, F.M. |
Title |
Structural ordering of self-assembled clusters with competing interactions : transition from faceted to spherical clusters |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Langmuir: the ACS journal of surfaces and colloids |
Abbreviated Journal |
Langmuir |
Volume |
31 |
Issue |
31 |
Pages |
917-924 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The self-assembly of nanoparticles into clusters and the effect of the different parameters of the competing interaction potential on it are investigated. For a small number of particles, the structural organization of the clusters is almost unaffected by the attractive part of the potential, and for an intermediate number of particles the configuration strongly depends on the strength of it. The cluster size is controlled by the range of the interaction potential, and the structural arrangement is guided by the strength of the potential: i.e., the self-assembled cluster transforms from a faceted configuration at low strength to a spherical shell-like structure at high strength. Nonmonotonic behavior of the cluster size is found by increasing the interaction range. An approximate analytical expression is obtained that predicts the smallest cluster for a specific set of potential parameters. A Mendeleev-like table is constructed for different values of the strength and range of the attractive part of the potential in order to understand the structural ordering of the ground-state configuration of the self-assembled clusters. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000348689700005 |
Publication Date |
2014-12-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0743-7463;1520-5827; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.833 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem programme of the Flemish government. Computational resources were provided by the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC). ; |
Approved |
Most recent IF: 3.833; 2015 IF: 4.457 |
Call Number |
c:irua:125292 |
Serial |
3243 |
Permanent link to this record |
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|
Author |
van der Stam, W.; Berends, A.C.; Rabouw, F.T.; Willhammar, T.; Ke, X.; Meeldijk, J.D.; Bals, S.; de Donega, C.M. |
Title |
Luminescent CuInS2 quantum dots by partial cation exchange in Cu2-xS nanocrystals |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
27 |
Issue |
27 |
Pages |
621-628 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Here, we show successful partial cation exchange reactions in Cu2-xS nanocrystals (NCs) yielding luminescent CuInS2 (CIS) NCs. Our approach of mild reaction conditions ensures slow Cu extraction rates, which results in a balance with the slow In incorporation rate. With this method, we obtain CIS NCs with photoluminescence (PL) far in the near-infrared (NIR), which cannot be directly synthesized by currently available synthesis protocols. We discuss the factors that favor partial, self-limited cation exchange from Cu2-xS to CIS NCs, rather than complete cation exchange to In2S3. The product CIS NCs have the wurtzite crystal structure, which is understood in terms of conservation of the hexagonal close packing of the anionic sublattice of the parent NCs into the product NCs. These results are an important step toward the design of CIS NCs with sizes and shapes that are not attainable by direct synthesis protocols and may thus impact a number of potential applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000348618400028 |
Publication Date |
2014-12-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
119 |
Open Access |
OpenAccess |
Notes |
335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 9.466; 2015 IF: 8.354 |
Call Number |
c:irua:125291 |
Serial |
1858 |
Permanent link to this record |
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|
|
Author |
Sathiya, M.; Abakumov, A.M.; Foix, D.; Rousse, G.; Ramesha, K.; Saubanère, M.; Doublet, M. .; Vezin, H.; Laisa, C.P.; Prakash, A.S.; Gonbeau, D.; Van Tendeloo, G.; Tarascon, J.M. |
Title |
Origin of voltage decay in high-capacity layered oxide electrodes |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
Volume |
14 |
Issue |
14 |
Pages |
230-238 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Although Li-rich layered oxides (Li1+xNiyCozMn1−x−y−zO2 > 250 mAh g−1) are attractive electrode materials providing energy densities more than 15% higher than todays commercial Li-ion cells, they suffer from voltage decay on cycling. To elucidate the origin of this phenomenon, we employ chemical substitution in structurally related Li2RuO3 compounds. Li-rich layered Li2Ru1−yTiyO3 phases with capacities of ~240 mAh g−1 exhibit the characteristic voltage decay on cycling. A combination of transmission electron microscopy and X-ray photoelectron spectroscopy studies reveals that the migration of cations between metal layers and Li layers is an intrinsic feature of the chargedischarge process that increases the trapping of metal ions in interstitial tetrahedral sites. A correlation between these trapped ions and the voltage decay is established by expanding the study to both Li2Ru1−ySnyO3 and Li2RuO3; the slowest decay occurs for the cations with the largest ionic radii. This effect is robust, and the finding provides insights into new chemistry to be explored for developing high-capacity layered electrodes that evade voltage decay. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000348600200024 |
Publication Date |
2014-12-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
39.737 |
Times cited |
395 |
Open Access |
|
Notes |
246791 Countatoms; 312483 Esteem2; esteem2_ta |
Approved |
Most recent IF: 39.737; 2015 IF: 36.503 |
Call Number |
c:irua:132555 c:irua:132555 |
Serial |
2528 |
Permanent link to this record |
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|
Author |
Zhang, L.-F.; Covaci, L.; Peeters, F.M. |
Title |
Position-dependent effect of non-magnetic impurities on superconducting properties of nanowires |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
Volume |
109 |
Issue |
109 |
Pages |
17010 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Anderson's theorem states that non-magnetic impurities do not change the bulk properties of conventional superconductors. However, as the dimensionality is reduced, the effect of impurities becomes more significant. Here we investigate superconducting nanowires with diameter comparable to the Fermi wavelength $\lambda_F$ (which is less than the superconducting coherence length) by using a microscopic description based on the Bogoliubov-de Gennes method. We find that: 1) impurities strongly affect the superconducting properties, 2) the effect is impurity position dependent, and 3) it exhibits opposite behavior for resonant and off-resonant wire widths. We show that this is due to the interplay between the shape resonances of the order parameter and the subband energy spectrum induced by the lateral quantum confinement. These effects can be used to manipulate the Josephson current, filter electrons by subband and investigate the symmetries of the superconducting subband gaps. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Paris |
Editor |
|
Language |
|
Wos |
000348592100029 |
Publication Date |
2015-01-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0295-5075 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.957 |
Times cited |
7 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Methusalem funding of the Flemish Government. ; |
Approved |
Most recent IF: 1.957; 2015 IF: 2.095 |
Call Number |
UA @ lucian @ c:irua:128424 |
Serial |
4227 |
Permanent link to this record |
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|
|
Author |
Zhang, L.-F.; Covaci, L.; Peeters, F.M. |
Title |
Tomasch effect in nanoscale superconductors |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
91 |
Issue |
91 |
Pages |
024508 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The Tomasch effect (TE) is due to quasiparticle interference (QPI) as induced by a nonuniform superconducting order parameter, which results in oscillations in the density of states (DOS) at energies above the superconducting gap. Quantum confinement in nanoscale superconductors leads to an inhomogenerous distribution of the Cooperpair condensate, which, as we found, triggers the manifestation of a new TE. We investigate the electronic structure of nanoscale superconductors by solving the Bogoliubov-de Gennes (BdG) equations self-consistently and describe the TE determined by two types of processes, involving two-or three-subband QPIs. Both types of QPIs result in additional BCS-like Bogoliubov-quasiparticles and BCS-like energy gaps leading to oscillations in the DOS and modulated wave patterns in the local density of states. These effects are strongly related to the symmetries of the system. A reduced 4 x 4 inter-subband BdG Hamiltonian is established in order to describe analytically the TE of two-subband QPIs. Our study is relevant to nanoscale superconductors, either nanowires or thin films, Bose-Einsten condensates, and confined systems such as two-dimensional electron gas interface superconductivity. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000348473700003 |
Publication Date |
2015-01-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Methusalem funding of the Flemish Government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
c:irua:123864 |
Serial |
3670 |
Permanent link to this record |
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Author |
Kolev, S.; Bogaerts, A. |
Title |
A 2D model for a gliding arc discharge |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
24 |
Issue |
24 |
Pages |
015025 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this study we report on a 2D fluid model of a gliding arc discharge in argon. Despite the 3D nature of the discharge, 2D models are found to be capable of providing very useful information about the operation of the discharge. We employ two modelsan axisymmetric and a Cartesian one. We show that for the considered experiment and the conditions of a low current arc (around 30 mA) in argon, there is no significant heating of the cathode surface and the discharge is sustained by field electron emission from the cathode accompanied by the formation of a cathode spot. The obtained discharge power and voltage are relatively sensitive to the surface properties and particularly to the surface roughness, causing effectively an amplification of the normal electric field. The arc body and anode region are not influenced by this and depend mainly on the current value. The gliding of the arc is modelled by means of a 2D Cartesian model. The arcelectrode contact points are analysed and the gliding mechanism along the electrode surface is discussed. Following experimental observations, the cathode spot is simulated as jumping from one point to another. A complete arc cycle is modelled from initial ignition to arc decay. The results show that there is no interaction between the successive gliding arcs. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000348298200026 |
Publication Date |
2014-12-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
34 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
Call Number |
c:irua:122538 c:irua:122538 c:irua:122538 c:irua:122538 |
Serial |
3 |
Permanent link to this record |
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Author |
Kozák, T.; Bogaerts, A. |
Title |
Evaluation of the energy efficiency of CO2 conversion in microwave discharges using a reaction kinetics model |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
24 |
Issue |
24 |
Pages |
015024 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We use a zero-dimensional reaction kinetics model to simulate CO2 conversion in microwave discharges where the excitation of the vibrational levels plays a significant role in the dissociation kinetics. The model includes a description of the CO2 vibrational kinetics, taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is used to simulate a general tubular microwave reactor, where a stream of CO2 flows through a plasma column generated by microwave radiation. We study the effects of the internal plasma parameters, namely the reduced electric field, electron density and the total specific energy input, on the CO2 conversion and its energy efficiency. We report the highest energy efficiency (up to 30%) for a specific energy input in the range 0.41.0 eV/molecule and a reduced electric field in the range 50100 Td and for high values of the electron density (an ionization degree greater than 10−5). The energy efficiency is mainly limited by the VT relaxation which contributes dominantly to the vibrational energy losses and also contributes significantly to the heating of the reacting gas. The model analysis provides useful insight into the potential and limitations of CO2 conversion in microwave discharges. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000348298200025 |
Publication Date |
2014-12-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
100 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
Call Number |
c:irua:122243 |
Serial |
1087 |
Permanent link to this record |
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Author |
Euan-Diaz, E.; Herrera-Velarde, S.; Misko, V.R.; Peeters, F.M.; Castaneda-Priego, R. |
Title |
Structural transitions and long-time self-diffusion of interacting colloids confined by a parabolic potential |
Type |
A1 Journal article |
Year |
2015 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
142 |
Issue |
142 |
Pages |
024902 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We report on the ordering and dynamics of interacting colloidal particles confined by a parabolic potential. By means of Brownian dynamics simulations, we find that by varying the magnitude of the trap stiffness, it is possible to control the dimension of the system and, thus, explore both the structural transitions and the long-time self-diffusion coefficient as a function of the degree of confinement. We particularly study the structural ordering in the directions perpendicular and parallel to the confinement. Further analysis of the local distribution of the first-neighbors layer allows us to identify the different structural phases induced by the parabolic potential. These results are summarized in a structural state diagram that describes the way in which the colloidal suspension undergoes a structural re-ordering while increasing the confinement. To fully understand the particle dynamics, we take into account hydrodynamic interactions between colloids; the parabolic potential constricts the available space for the colloids, but it does not act on the solvent. Our findings show a non-linear behavior of the long-time self-diffusion coefficient that is associated to the structural transitions induced by the external field. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000348129700053 |
Publication Date |
2015-01-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9606;1089-7690; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.965 |
Times cited |
7 |
Open Access |
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Notes |
; This work was partially supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), PIFI 3.4 – PROMEP, and CONACyT (Grant Nos. 61418/2007, 102339/2008, Ph.D. scholarship 230171/2010). R.C.-P. also acknowledges financial support provided by the Marcos Moshinsky fellowship 2013-2014. The authors also thank to the General Coordination of Information and Communications Technologies (CGSTIC) at Cinvestav for providing HPC resources on the Hybrid Cluster Super-computer Xiuhcoatl, which have contributed partially to the research results reported in this paper. ; |
Approved |
Most recent IF: 2.965; 2015 IF: 2.952 |
Call Number |
c:irua:123832 |
Serial |
3267 |
Permanent link to this record |
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Author |
van der Stam, W.; Akkerman, Q.A.; Ke, X.; van Huis, M.A.; Bals, S.; de Donega, C.M. |
Title |
Solution-processable ultrathin size- and shape-controlled colloidal Cu2-xS nanosheets |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
27 |
Issue |
27 |
Pages |
283-291 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Ultrathin two-dimensional (2D) nanosheets (NSs) possess extraordinary properties that are attractive for both fundamental studies and technological devices. Solution-based bottom-up methods are emerging as promising routes to produce free-standing NSs, but the synthesis of colloidal NSs with well-defined size and shape has remained a major challenge. In this work, we report a novel method that yields 2 nm thick colloidal Cu2-xS NSs with well-defined shape (triangular or hexagonal) and size (100 nm to 3 mu m). The key feature of our approach is the use of a synergistic interaction between halides (Br or Cl) and copper-thiolate metal-organic frameworks to create a template that imposes 2D constraints on the Cu-catalyzed C-S thermolysis, resulting in nucleation and growth of colloidal 2D Cu2-xS NSs. Moreover, the NS composition can be postsynthetically tailored by exploiting topotactic cation exchange reactions. This is illustrated by converting the Cu2-xS NSs into ZnS and CdS NSs while preserving their size and shape. The method presented here thus holds great promise as a route to solution-processable compositionally diverse ultrathin colloidal NSs with well-defined shape and size. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000348085300036 |
Publication Date |
2014-12-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
68 |
Open Access |
OpenAccess |
Notes |
335078 Colouratom; 246791 Countatoms; 312483 Esteem2; esteem2ta; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 9.466; 2015 IF: 8.354 |
Call Number |
c:irua:123865 c:irua:123865 |
Serial |
3052 |
Permanent link to this record |
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Author |
van Dyck, D.; Lobato, I.; Chen, F.-R.; Kisielowski, C. |
Title |
Do you believe that atoms stay in place when you observe them in HREM? |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Micron |
Abbreviated Journal |
Micron |
Volume |
68 |
Issue |
68 |
Pages |
158-163 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Recent advancements in aberration-corrected electron microscopy allow for an evaluation of unexpectedly large atom displacements beyond a resolution limit of similar to 0.5 angstrom, which are found to be dose-rate dependent in high resolution images. In this paper we outline a consistent description of the electron scattering process, which explains these unexpected phenomena. Our approach links thermal diffuse scattering to electron beam-induced object excitation and relaxation processes, which strongly contribute to the image formation process. The effect can provide an explanation for the well-known contrast mismatch (“Stobbs factor”) between image calculations and experiments. (C) 2014 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000348016500023 |
Publication Date |
2014-09-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0968-4328; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.98 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.98; 2015 IF: 1.988 |
Call Number |
c:irua:123802 |
Serial |
745 |
Permanent link to this record |
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Author |
Kirilenko, D.A.; Dideykin, A.T.; Aleksenskiy, A.E.; Sitnikova, A.A.; Konnikov, S.G.; Vul', A.Y. |
Title |
One-step synthesis of a suspended ultrathin graphene oxide film: Application in transmission electron microscopy |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Micron |
Abbreviated Journal |
Micron |
Volume |
68 |
Issue |
68 |
Pages |
23-26 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Ultrathin graphene films find their use as advantageous support for nano- and biomaterials investigations. Thin film causes a very slight deterioration to measured signals, thus providing more details of the object's structure at nanoscale. The ultimate thinness of graphene works in the best way for this purpose. However, obtaining suspended thin film of a large-area, which is convenient for applications, is often a relatively complicated and time-consuming task. Here we present a one-step 1-min technique for synthesis of an extremely thin (about 1-2 nm) continuous film suspended over cells of a conventional copper grid (50-400 mu m mesh). This technique enables us to acquire a large-area film which is water-resistant, stable in organic solvents and can act as a support when studying nanoparticles or biomaterials. Moreover, the very mechanism of the film formation can be interesting from the point of view of other applications of ultrathin graphene oxide papers. (C) 2014 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000348016500004 |
Publication Date |
2014-08-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0968-4328; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.98 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.98; 2015 IF: 1.988 |
Call Number |
c:irua:123800 |
Serial |
2467 |
Permanent link to this record |
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Author |
Gul, B.; Tinck, S.; De Schepper, P.; Aman-ur-Rehman; Bogaerts, A. |
Title |
Numerical investigation of HBr/He transformer coupled plasmas used for silicon etching |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
48 |
Issue |
48 |
Pages |
025202 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A two-dimensional hybrid Monte Carlofluid model is applied to study HBr/He inductively coupled plasmas used for etching of Si. Complete sets of gas-phase and surface reactions are presented and the effects of the gas mixing ratio on the plasma characteristics and on the etch rates are discussed. A comparison with experimentally measured etch rates is made to validate the modelling results. The etch rate in the HBr plasma is found to be quite low under the investigated conditions compared to typical etch rates of Si with F- or Cl-containing gases. This allows for a higher control and fine-tuning of the etch rate when creating ultra-small features. Our calculations predict a higher electron temperature at higher He fraction, because the electrons do not lose their energy so efficiently in vibrational and rotational excitations. As a consequence, electron impact ionization and dissociation become more important, yielding higher densities of ions, electrons and H atoms. This results in more pronounced sputtering of the surface. Nevertheless, the overall etch rate decreases upon increasing He fraction, suggesting that chemical etching is still the determining factor for the overall etch rate. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000347980100011 |
Publication Date |
2014-12-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2015 IF: 2.721 |
Call Number |
c:irua:121335 |
Serial |
2394 |
Permanent link to this record |